As I write, it is still Constitution Day, designated to celebrate the day in 1787 that the memebers of the constitutional conventions signed the final document. Now I don't think the U.S. Constitution is a perfect document. Having read pretty deeply in the history, I'm pretty sure I would have been what is now called an "anti-federalist" (inaccurately because the winners usually get to pick the labels; at the time the constitution advocates were the centralists in the argument). I would have been afraid that the constitution, as assiduously as it tried to establish a strictly limited government with only limited enumerated powers, gave the central government more power than is healthy. I think our history has borne this fear out pretty well. They started stretching the limits of legitimate power almost from the first year (but we were fortunate to have Washington, who really did believe in limited government and established some healthy traditions and attitudes).
Still, despite having stretched, tattered and sometimes shredded, the constitution is still a valuable document and still capable of protecting our liberties. I think this Register editorial expresses the pros and cons rather nicely, if I do say so myself.
That Cato Institute for the last several years has chosen Constitution Day to do its annual Supreme Court review and preview. I was fortunate to be able to attend it last year, and found the interchange (they invite lawyers and professors of various persuasions) informative and intellectually stimulating -- and useful, given that I write most of the Supreme Court editorials at the Register.